The invention relates to an arrangement for handling sheet-like articles, in particular an envelope-filling station in mail-processing machines, according to the preamble of claim 1.
Known envelope-filling stations of the type under consideration here contain an actuating arrangement, which has at least one drive lever which is mounted pivotably on the framework at its top end and of which the bottom end is in connection with handling elements which can be moved backward and forward in a conveying direction over a horizontal base plate, and also contain a drive mechanism, which drives the at least one drive lever in a forward pivoting movement for carrying out an operating stroke, and in a backward pivoting movement for carrying out a return stroke, of the handling elements.
WO 99/01295 A1 discloses an arrangement for handling sheet-like articles which has the features of the preamble of patent claim 1. In this known arrangement, the drive-lever arrangement is in the form of a three-lever rectilinear-guidance mechanism. One of the levers which forms part of said three-lever rectilinear-guidance mechanism, is in connection with the handling elements at its bottom end, and is mounted pivotably on the framework at its top end, is connected integrally to an auxiliary drive lever which projects away at an angle from a main part of said lever and is connected to a connecting rod, which is coupled to the crank and the crankshaft of the drive mechanism.
In the case of an increase in the operating speed of the arrangement, in the case of unexpected changes in the properties and behavior of the articles which are to handled, and in the case of operational disruptions and the like caused by the ingress of foreign bodies, it may be that, during the operating stroke, the push-in fingers cannot complete their route over the base plate and catch on the base plate or on cutouts thereof, or on the articles which are to be conveyed, and that this damages the actuating arrangement and/or its drive mechanism. Damage to the actuating arrangement on account of blocking of the push-in fingers during the operating stroke thereof is all the more probable the finer the members of said actuating arrangement are, for the purpose of reducing the moving masses at elevated operating speeds and, for example, of reducing the overall height.
The invention is intended to achieve the object of configuring an arrangement for handling sheet-like articles of the general type described in the introduction so as reliably to avoid, in all phases of the operating stroke, an overloading of parts of the apparatus in the case of blocking of the handling elements during said operating stroke.
This object is achieved according to the invention by the features specified in claim 1.
Advantageous configurations and developments are defined in the claims following claim 1 and, without the wording thereof being repeated here, the contents of these claims hereby expressly form a constituent part of the description.